Power devices are utilized in a plurality of circuit applications that require high voltage and current capability, for example, automotive circuits. However, even power devices must be protected from large surge currents which could destroy the device.
Control circuits are typically utilized to protect power devices by monitoring the current flowing through the power device. Further, most control circuits for power devices are voltage driven. However, the disadvantage of voltage driven control circuits is that they are much more susceptible to voltage transients, for example, transients that are ground bounce induced.
One type of current driven control circuit is fully described in U.S. Pat. No. 5,006,736, having an issue date of Apr. 9, 1991. This patent describes a control circuit for both limiting the gate voltage of a power device and discharging the gate-source capacitance of the power device. However, this patent does not teach utilizing additional control circuitry for detecting over-current or over-temperature conditions of the power device.
Hence, there is a need for an improved current driven circuit for controlling a power device and detecting over-current and over-temperature conditions of the power device.